I don't know if this is related to the display of a "drift" off the LNAV route, but here I am flying from KSFO direct DPA (near KORD). The FMC says the course is 71

Lee-identified, thanks!

Lefteris,Sort of related - does the ND display really delete waypoints you've passed from the screen and draw a new straight line to the next waypoint through the screen? I really think that it might continue displaying the previous waypoints - in fact I think I remember reading that Boeing made this change in a software revision folowing the crash of an American 757 in Columbia where the pilots had already passed a VOR, but had lost situational awareness and didn't realize they'd passed it because only the active waypoint and ones past it were being displayed.Look at these pics http://www.airliners.net/open.file/326896/L/ http://www.airliners.net/open.file/294126/L/ - that seems to be an already passed waypoint at the bottom of the ND. (turns white after being passed - active is magenta) Right after they pass the active waypoint here, shouldn't that whole magenta line stay exactly the same way that it is (but just rotate it's orientation) as the plane turns toward the next fix? In the sim right now, the previous portion of the magenta line gets erased and a new straight line is drawn along the course that the plane is turning to - it's like it always needs to have a straight down pointing line or something - doesn't seem right to me.I'll take some screen shots in a bit to further illustrate what I'm saying about it drawing a new straight line, it's kind of hard to describe in words alone...Ryan

Lefteris, thanks.Lee Hetherington (KBED)

I was wondering the exact same thing and figured it was just an NG thing. Now, seeing real NG pictures makes me really wonder. It really does hurt situational awareness on the map to have the past suddenly disappear. Personally, I don't like that behavior.Lee Hetherington (KBED)

Ok here's exactly what I'm talking about:I've just departed KPHX on the CHEZZ2.DRYHT DP, and I'm about to pass the CHEZZ fix and turn toward CLOSE.http://forums.avsim.com/user_files/23056.jpgRight as the plane begins to turn toward CLOSE, the ND stops displaying CHEZZ and draws a new straight line along the course it calculates between CHEZZ and CLOSE.http://forums.avsim.com/user_files/23058.jpgIt really seems to me that it shouldn't be drawing that new straight line - the passed fix and the line segment connecting them should remain and just rotate/translate in orientation as necessary. I know this isn't a 767, but PIC's EHSI does behave exactly the way I'm describing and I believe that to be way it actually works...Thanks for looking into this stuff!Ryan

Just want to chime in that I have noticed this behavior and also found it odd.Jeff